main{
	width: 900px;
	margin: 50px auto;
}
h1{
	margin: 0;
	font-size: 1.2rem;
	text-align: left;
	margin-bottom: 20px;
}
#table1{
	width: 500px;
}
#table1 td:nth-child(1){
	width: 130px;
}
#table1 td:nth-child(2){
	width: 185px;
}
#table1 td{
	height: 30px;
	font-size: .9rem;
}
/*属性选择器*/
input[type=text]{
	width: 165px;
	height: 25px;
	background-color: #eff8ff;
	border: 1px solid darkgrey;
}
select{
	width: 163px;
	background-color: #eff8ff;
	border: 1px solid darkgray;
	height: 25px;
	font-size: 1resm;
}
input[type=button]{
	width: 163px;
}
form{
	float: left;
}
section{
	float: right;
}
h4{
	margin: 0 0 20px 0;
	font-size: .9rem;
	text-align: left;
}
#table2{
	/*间隔合并*/
	border-spacing: 0 0;
}
#table2 td:nth-child(1){
	width: 100px;
	text-align: center;
}
#table2 td:nth-child(2){
	width: 200px;
	text-align: center;
}
td{
	height: 25px;
	font-size: .9rem;
}
#table2 tr:nth-child(1){
	font-weight: bold;
	background-color:  #8DD8F8;
	
}
#table2 tr:nth-child(2){
	background-color:  #CCCCCC;
	
}
#table2 tr:nth-child(3){
	background-color:  #66CC00;
	
}
#table2 tr:nth-child(4){
	background-color:  #FFFF00;
	
}
#table2 tr:nth-child(5){
	background-color:  #FF9900;
	
}
/*被隐藏的结果样式*/
#result{
	height: 40px;
	/*rem相对于跟标签的字体来说的,跟标签的字体默认16px*/
	font-size: 1.1rem;
	border: 1px dotted gray;
	background-color: #FFFFAA;
	margin-bottom: 20px;
	display: none;
}
#BMI-value{
	color: green;
	font-weight: bold;
}















